chore: Using MemoryStorage in a WASM environment

Author: KKould

.cargo/config.toml

@@ -0,0 +1,2 @@
+[target.wasm32-unknown-unknown]
+rustflags = ["--cfg=getrandom_backend=\"wasm_js\""]

Cargo.lock

@@ -21,6 +21,7 @@ required-features = ["net"]
 
 [lib]
 doctest = false
+crate-type = ["cdylib", "rlib"]
 
 [features]
 default = ["macros"]
@@ -40,7 +41,7 @@ bincode               = { version = "1" }
 bumpalo               = { version = "3", features = ["allocator-api2", "collections", "std"] }
 byteorder             = { version = "1" }
 chrono                = { version = "0.4" }
-comfy-table           = { version = "7" }
+comfy-table           = { version = "7", default-features = false }
 csv                   = { version = "1" }
 fixedbitset           = { version = "0.4" }
 itertools             = { version = "0.12" }
@@ -50,7 +51,6 @@ parking_lot           = { version = "0.12", features = ["arc_lock"] }
 petgraph              = { version = "0.6" }
 recursive             = { version = "0.1" }
 regex                 = { version = "1" }
-rocksdb               = { version = "0.23" }
 rust_decimal          = { version = "1" }
 serde                 = { version = "1", features = ["derive", "rc"] }
 kite_sql_serde_macros = { version = "0.1.0", path = "kite_sql_serde_macros" }
@@ -60,7 +60,6 @@ thiserror             = { version = "1" }
 typetag               = { version = "0.2" }
 ulid                  = { version = "1", features = ["serde"] }
 genawaiter            = { version = "0.99" }
-rand                  = { version = "0.8" }
 
 # Feature: net
 async-trait           = { version = "0.1", optional = true }
@@ -84,11 +83,20 @@ pprof = { version = "0.13", features = ["flamegraph", "criterion"] }
 
 [target.'cfg(not(target_arch = "wasm32"))'.dependencies]
 dirs = { version = "5" }
+rocksdb = { version = "0.23" }
 
 [target.'cfg(target_arch = "wasm32")'.dependencies]
-wasm-bindgen = { version = "0.2" }
-web-sys      = { version = "0.3", features = ["Storage", "Window"] }
-base64       = { version = "0.21" }
+wasm-bindgen        = { version = "0.2" }
+web-sys             = { version = "0.3", features = [
+    "Storage",
+    "Window",
+] }
+base64              = { version = "0.21" }
+getrandom           = { version = "0.2", features = ["js"] }
+getrandom_03        = { package = "getrandom", version = "0.3", features = ["wasm_js"] }
+js-sys              = { version = "0.3" }
+serde-wasm-bindgen  = { version = "0.6" }
+once_cell           = { version = "1" }
 
 [target.'cfg(target_arch = "wasm32")'.dev-dependencies]
 wasm-bindgen-test = "0.3"
@@ -102,3 +110,6 @@ members = [
 
 [profile.release]
 lto = true
+
+[package.metadata.wasm-pack.profile.release]
+wasm-opt = false

Cargo.toml

@@ -34,9 +34,24 @@
 - All metadata and actual data in KV Storage, and there is no state component (e.g. system table) in the middle
 - Supports extending storage for customized workloads
 - Supports most of the SQL 2016 syntax
+- Ships a WebAssembly build for JavaScript runtimes
 
 #### 👉[check more](docs/features.md)
 
+## WebAssembly
+- Build: `wasm-pack build --release --target nodejs` (outputs to `./pkg`; use `--target web` or `--target bundler` for browser/bundler setups).
+- Usage:
+```js
+import { WasmDatabase } from "./pkg/kite_sql.js";
+
+const db = new WasmDatabase();
+await db.execute("create table demo(id int primary key, v int)");
+await db.execute("insert into demo values (1, 2), (2, 4)");
+const rows = db.run("select * from demo").rows();
+console.log(rows.map((r) => r.values.map((v) => v.Int32 ?? v)));
+```
+- In Node.js, provide a small `localStorage` shim if you enable statistics-related features (see `examples/wasm_index_usage.test.mjs`).
+
 ## Examples
 
 ```rust

README.md

@@ -28,19 +28,48 @@ implement_from_tuple!(
 fn main() -> Result<(), DatabaseError> {
     let database = DataBaseBuilder::path("./hello_world").build()?;
 
+    // 1) Create table and insert multiple rows with mixed types.
     database
-        .run("create table if not exists my_struct (c1 int primary key, c2 int)")?
+        .run(
+            "create table if not exists my_struct (
+                c1 int primary key,
+                c2 varchar,
+                c3 int
+            )",
+        )?
         .done()?;
     database
-        .run("insert into my_struct values(0, 0), (1, 1)")?
+        .run(
+            r#"
+        insert into my_struct values
+            (0, 'zero', 0),
+            (1, 'one', 1),
+            (2, 'two', 2)
+        "#,
+        )?
         .done()?;
 
+    // 2) Update and delete demo.
+    database
+        .run("update my_struct set c3 = c3 + 10 where c1 = 1")?
+        .done()?;
+    database.run("delete from my_struct where c1 = 2")?.done()?;
+
+    // 3) Query and deserialize into Rust struct.
     let iter = database.run("select * from my_struct")?;
     let schema = iter.schema().clone();
 
     for tuple in iter {
         println!("{:?}", MyStruct::from((&schema, tuple?)));
     }
+
+    // 4) Aggregate example.
+    let mut agg = database.run("select count(*) from my_struct")?;
+    if let Some(count_row) = agg.next() {
+        println!("row count = {:?}", count_row?);
+    }
+    agg.done()?;
+
     database.run("drop table my_struct")?.done()?;
 
     Ok(())

examples/hello_world.rs

@@ -5,6 +5,7 @@ fn main() -> Result<(), DatabaseError> {
     let database = DataBaseBuilder::path("./transaction").build_optimistic()?;
     let mut transaction = database.new_transaction()?;
 
+    // Scenario: create table and insert rows inside a transaction; visible after commit.
     transaction
         .run("create table if not exists t1 (c1 int primary key, c2 int)")?
         .done()?;
@@ -18,6 +19,21 @@ fn main() -> Result<(), DatabaseError> {
 
     assert!(database.run("select * from t1").is_ok());
 
+    // Scenario: another transaction updates but does not commit; changes stay invisible.
+    let mut tx2 = database.new_transaction()?;
+    tx2.run("update t1 set c2 = 99 where c1 = 0")?.done()?;
+    assert_eq!(
+        database
+            .run("select c2 from t1 where c1 = 0")?
+            .next()
+            .unwrap()?
+            .values[0]
+            .i32(),
+        Some(0)
+    );
+    // rollback
+    drop(tx2);
+
     database.run("drop table t1")?.done()?;
 
     Ok(())

examples/transaction.rs

@@ -0,0 +1,49 @@
+// Simple wasm smoke test; run `wasm-pack build --target nodejs` first to generate ./pkg
+import assert from "node:assert/strict";
+import { createRequire } from "module";
+
+const require = createRequire(import.meta.url);
+const { WasmDatabase } = require("../pkg/kite_sql.js");
+
+async function main() {
+  const db = new WasmDatabase();
+
+  await db.execute("drop table if exists my_struct");
+  await db.execute("create table my_struct (c1 int primary key, c2 int)");
+  await db.execute("insert into my_struct values(0, 0), (1, 1)");
+
+  const rows = db.run("select * from my_struct").rows();
+  assert.equal(rows.length, 2, "should return two rows");
+
+  const [first, second] = rows;
+  const firstVals = first.values.map((v) => v.Int32 ?? v);
+  const secondVals = second.values.map((v) => v.Int32 ?? v);
+  assert.deepEqual(firstVals, [0, 0]);
+  assert.deepEqual(secondVals, [1, 1]);
+
+  await db.execute("update my_struct set c2 = c2 + 10 where c1 = 1");
+  const after = db.run("select c2 from my_struct where c1 = 1").rows();
+  assert.deepEqual(after[0].values.map((v) => v.Int32 ?? v), [11]);
+
+  // Stream the rows using the iterator interface
+  const stream = db.run("select * from my_struct");
+  const streamed = [];
+  let row = stream.next();
+  while (row !== undefined) {
+    streamed.push(row.values.map((v) => v.Int32 ?? v));
+    row = stream.next();
+  }
+  stream.finish();
+  assert.deepEqual(streamed, [
+    [0, 0],
+    [1, 11],
+  ]);
+
+  await db.execute("drop table my_struct");
+  console.log("wasm hello_world test passed");
+}
+
+main().catch((err) => {
+  console.error(err);
+  process.exit(1);
+});